Dental casting-machine.



E. E. WIGHTMAN.

DENTAL CASTING MACHINE.

APPLICATION man MAR. 10. 1916.

1,230,254. Patented June 19, 1917.

MEL li zz 6 ELMER E. WIGHTMAN, OF CHICAGO, ILLINOIS.

DENTAL CASTIN G- MAGHIN E.

Specification of Letters Patent.

Patented June 19, 1917.

Application filed March 10, 1916. Serial No. 83,258.

To all whom it may concern:

Be it known that I, ELMER E. WIGHT-I MAN, a citizen of the UnitedStates, and a panying drawings, and to the numerals of reference,- marked thereon, which form a part of this specification.

Difliculty has been experienced which metallic inlays for teeth are formed,

owing to the multiplicity of operations necessary during the process of molding the inlay or other article, as the case may be. This invention relatesto animprovedtype of casting apparatus wherein the number of operations necessary onthe part ofthe personmaking the mold and casting the inlay is reduced to a minimum,'so that the successful production of a casting is assured with a high degree of efliciency. Heretofore the multiplicity of operations which have been necessary, as for instance, the continuous pumping for creating j a suctlon, have required so much of the time and attention of a person using the apparatus that the metal, particularly where gold has been used, has solidified prematurely and as a consequence liability of an imperfect casting is the result.

It is an object therefore of this invention to construct an improved type of dental casting apparatus wherein means are provided for creating a direct suction in a dental mold to facilitate the casting operationand insure the formation of a substantially perfect product.

It is also an object of this invention to construct a dental apparatus adapted to operate efficiently in facilitating the produc- Ition of a dental casting or inlay, wherein the number of operations on the part of the person using the apparatus is reduced to a minimum and the production of a successful inlay from the mold, assured It is furthermore-an 'obje'ctof this tion to construct a dental apparatus comprising'means to receive a small flaskcontaining the mold-sealingly mounted on S2116. means, with a foot operated suction producing" mechanism conveniently associated heretofore in the use of dental casting apparatus by inventherewith, and with mechanisms acting automati'cally when released to permit a strong suction effect upon the mold within the flask to facilitate entrance thereinto of a fused metal 'to be cast in the'mold into an inlay or other article; 7

It is finally an object of this invention to construct an improved type of dental apparatus consisting of few parts and with the parts arranged for convenient operation, permitting work to be performed with the greatest degree of efliciency and minimum number of operations.

The invention (in a preferred form) is illustrated in the drawings and hereinafter more fully described.

In the drawings:

Figure l is a view partly in section and partly in elevation of the assembled parts of the apparatus embodying the principles of my invention 7 Fig. 2 is a detail section taken on line 2 2 of Fig. 1.

Fig. 3 is a fragmentary detail section taken on line 33 of Fig. '2.

Fig, 4 is a'detail section taken on line 4-4 of Fig. 1. I

Fig. 5 is a view wit parts in section,

taken on line 55 of Fig. 4.

Fig. 6 is a sectional detail view of a modified form of flask for a different type of therefrom are a pair of uprights 5. Secured to and supported upon the upper ends of said uprights 5, is a cylinder 6, the upper end of which receives threaded-therein said pipe 2. Movable within'said cylinder 6 is a piston 7, having secured thereto and extending downwardly therefrom a piston rod 8, which extends through the lower end of the cylinder and is pivotally connected to'a 'foot pedal 9, slidableupon said uprights 5, and the forward end of which is provided with a rounded shoe 10, engaging movably beneath a roller 11, mounted in lugs at the forward end of the base plate 4. In order to resist tension of the valve '3, to support the=flaslr downward movement of said pedal 9,"as well as said piston 7, Within the cylinder, coiled tension springs 12, are connected 0n-'eXteI1 sions on each side of the pedal 9, and to lugs provided at the upper endof the cylinder 6. The rotatable plug valve 3, is provided with an-actuating handle or lever 13, connected on one end of which is aitension spring 14, having its other end connected to a fixed point in the top :of the table or. bench, 1, and. disposed to latch over the other, end ofsaid leveror handle .13, is spring impelled pawl15,pivotally mounted at thev top :sunface of .the table topand impelled forwardly by a leaf spring 16, mountedadjacent thereto.

Secured inlthe uppervend of the valve \3, is

a vpipe :section. 17, having formed onsthe 1.113%

per end thereof" an enlarged cored out head, theexterior surface of whichis ground to a conical taper 1S, convergent upwardly, and the interior cored out: portion-of which is ground to a downwardly or inwardly convergen-t tape-r419. Shownlin Figs-1 and 2,.

is a flask 20, having aninterior perforated wall or partition 21, and with-thelower lend of.-:the:.-fias;l ground ;to a taper to fitwsealingly over the exterior. ground portion, 18, of thepipesection leading from the valve '3.

In Fig. 6, I have shown a modified type of flask denoted by the reference numeral 22, having a tubular lower stem extension- 28, the exterior surface ofwhich is; ground to a taper adaptedto; fit. into. the interiorly ground-tapered portionu19, of the pipe exattached :thereon innplace o f the flask 20, and of course in sealing irelatlonthereon. A

" removable 1 perforated partition element 2 1,

is provided to=seat upon a shoulder. or ledge provided upon the interior ofcthe flash-22, to receive the plaster of Paris 25, orothermaterial of which the. mold isnmade' packed thereonwithin the flask... lnthe present instance the castingsorformed. in the mold is shown inisection, being denoted by the reference numeral 26. a

Means are provided-for latching the pedal; 9, in a depressed position.- againsta -suction ereateddnthe cylinder, as well as; thenstresssof 1the.,.-springs 12, and forthisnpurpose a pawl 27, isrpivoted in the .notchedrear. end of thebase plate :4, and normally impelled forward-ly by a leaf spring .28, andiis. adapted to'proj ect throughand engage over the up-.= per edge'rof; an aperture .29,--provided inthe. end of, the pedal 9.. I

The operation is as follows '2 In :malging a mold, the. usual procedure is followed, that. is, the material. of, which the mold is made-is packedintoeither one-(of the flasks.20.-or -22, as the easezrnaybe, with& the. wax v,p fttern therein, afterywhiehl the moldis, heated andthe wax pattern melted. away, Theafiask is then. mounted uponthe pipe extension 17, and the globule of metal placed on the surface of the mold in a pocket providedtherefor; as --usual, and fused by means of a blowpipe or other means so that the fused metal may flow downwardly through a gate, into the mold. Just as this operationis about to take place,- the-valve 3, is:openecl=-from .-the position shown in Fig.

.2, to release position by striking the latch 15, rearwardly to release'the handle 13,--of the=valve,,and-the springl, aotsunder tensionto rotate the val'veisuddenly into open position. .1 T his sudden -movement ofi the valve is-aimportant for thevreason that a strong} suction; .eifect is exerted immediately upon the mold andthefused metal flows iostantly, thereintoj without possibility I of premature solidification, Thepiston .7, in the cylinder 6, has of course been previ-v ously drawmdownwandly into-the lower jend of theeylinder by depression. of the pedal. 9, and retained by thellatching;oflsaid pedali withithepawl 27, so that-.the suction-created in the cylinder 6,r,.is exerted throughthe pipe i 2,. and open; valve 113, upon. the mold.- The preliminary o-pzerationsi=neoessaryfor using; the apparatus may be performed .beforehand,.that is,-the vaflvefi, closed and the piston: 7, drawn: tothe-.-l'ower1end of the cylinder-and the pedalr9, latched-in its lower position to thus maintain the...sucti0ncre-v ated! within the cylinder., It is then only necessary atthe prloperltimein the process to releasetheilatch 15, andrpermitthe 'suction-uto be exerted through. the porous materiailof the-mold within=the flask to-evacuatethe moldand insure an :easy, flow thereinto of; the molten, or fusedmetal of whichthe casting, is: to be'zmade... I

Thencylinder 6, is'of relatively 'large1ca' pacity, so that only onestreke .ofthe yPlStOII therein isynecessary to create a zsuflieient suction; for. one roasting zoperation', thus.obviating the continuous pumpingaoperationsas in the ease of pumps or other-means used heretofore. V Lamaaware that various detailsvof construction, may becvaried through a wide range without departinggfrom the principles ofwtliis invention, andlJ thereforedo notpurpose limiting the patent granted other wise than necessitated thev .prior art. Iclaim as myinvention p 1.; 111, an apparatus; of: the class described, a, suction produeing means mechanism in communication therewith adapted to.- receive a mold flask sealingly attached thereto, a valve located therebetweem, means for moving said valve toaopen'position,and-a latch adapted to; retain. said valve in 1 closed posi tion against the power of said; moving means;

2. In-an apparatus ofthe class described, a suction prod-ueing means, mechanism; in communication therewith adapted; to receive a mold. fiask seailingly, attached thereto, a,

valve located therebetiveen, a spring for moving said valve to open position, and a latch adapted to retain said valve in closed position against the tension of said spring.

3. In an apparatus of the class described, a suction pump, its piston, a treadle for operating said piston in one direction, springs for operating said piston in the return direction, a mold flask sealingly connected directly With said pump, and a quick operating valve self-opening When releasedto establish immediate communication between said pump cylinder. and said flask.

4. In an apparatus of the class described,

a suction producing means, and a head connected thereto having its exterior surface tapered conically and converging upwardly and having its interior cored out in a downward converging taper, either of said tapered portions adapted to receive a mold flask.

In testimony whereof I have hereunto subscribed my name in the presence of two subscribing Witnesses.

ELMER E. WIGHTMAN.

WVitnesses:

CHARLES W. HILLS, J r., EARL M. HARDINE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

